Satellite Ground Station

Andrew Keller Ranek Kiil Jacob Ortt Bryson Peeters

ECE 492 — Winter 2015

AlbertaSat RefresherSatellite: Ex-Alta 1

• Alberta’s first satellite

Mission: QB50

• collect scientific measurements in lower ionosphere

Mission Details

• 300-400 km

• Fluxgate magnetometer and Langmuir Probe

• ~2 year orbit

600 km

300 km

85 km

45 km

12 km

EXOSPHERE

THERMOSPHERE

MESOSPHERE

STRATOSPHERE

TROPOSPHERE

IONOSPHERE

E

F

ObjectivesAutomated & integrated solution to track satellite and communicate with it.

• Point antenna at and track satellite

• Tune radio to satellite’s frequency

• Store and decode signals from space

• Send commands to satellite when it passes

Tracking Communications

Orbit Prediction

• Satellites tracked by NORAD

• Orbital elements + time + location → azimuth and altitude

QB50P1 1 40025U 14033R 15097.15808165 .00003222 00000-0 36684-3 0 9997 2 40025 97.9587 357.3098 0014668 59.2887 300.9780 14.86830496 43246

N

E

S

W

Satellite

Station

Azimuth

Altitude

Ground Station Design

• Download orbital data from web

• PC predicts satellite passes

• Send (altitude, azimuth) to controller

• Controller turns rotator

Main PC

Rotator Controller

Antenna

Rotator Motor

Communications Overview• Ultra High Frequency (~430 MHz)

• Focus on downloading scientific data

• Two types of commands:

• real time

• scripted

Main PC

Terminal Node Controller

Radio

Satellite

CubeSat Space Protocol

• Similar to IP, but lighter weight

• 32 bit vs. 160 bit header

Bit offset

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0

0 Priority Source Destination Destination

PortSource Port Reserved

H M A C

X T E A

R D P

C R C

32 Data (0 – 65535 bytes)

Communications Demo

Results

- - - - - • - - • - - - - -T O K Y O

8-52-11 MINAMI-SENJYU ARAKAWA-KU TOKYO-TO JAPAN

Questions?